Ingredients:
Salt & pepper
1 cup canned button mushrooms, sliced
5 ounces cream of mushroom soup
2 servings pasta of choice
2 tablespoons butter
1/4 cup pasta water
1/3 cup Parmesan cheese (fresh is best, but packaged is the less expensive option)

Directions:
Season pasta water generously with salt, and cook pasta according to package instructions. Meanwhile, in a medium-sized pan on low heat, melt butter, and heat mushrooms 5 minutes to let them soften. Then, add cream of mushroom soup, and heat another 2 minutes. Remove 1/3 cup pasta water from pasta, and whisk it into the mushroom mixture. Add Parmesan, and whisk until fully melted into the sauce. Season mushroom sauce with salt and pepper to taste.

Drain the pasta, toss it in the sauce, and serve.